In a scene reminiscent of the worst days of the Troubles, two young men in Londonderry were ordered to appear before a self-appointed gang of vigilantes and shot in the legs.

The youths were lucky as the gang, Republican Action Against Drugs, has already killed one man as well as seriously wounding many others. The gang is acting with seeming impunity and creating considerable fear in the city and other parts of the north west of the province.

From the comments of the father of one of its latest victims it appears the gang is made up of former republicans. Certainly the kneecapping and threats against drug dealers ape the actions of the Provisional IRA which also took upon itself the duty of tackling anti-social behaviour in nationalist areas. Neither group ever seemed aware of the irony that their actions were even more despicable than those allegedly committed by their victims.

It is evident that a tougher police stance has to be taken against RAAD. Brave people within the nationalist community in Derry have spoken out against the group - one rally was held just before the two youths were shot - and the PSNI must demonstrate that it supports the law-abiding citizens.

The police need to show the same determination to get to grips with these gangsters as they did with the carjackers in Belfast. After all, if the police cannot enforce the law then they are giving credence to the vigilantes.

Sinn Fein has a major role to play as well. It is inconceivable that party members do not know at least some of the members of RAAD and should bring their influence to bear on them. It is not enough simply to condemn the shootings and say that the gangsters are not true republicans. In the new Northern Ireland, anyone with information about those responsible for the litany of attacks carried out by RAAD must give it to the PSNI. Only then can the gang's terror be stopped.